Just in case if FATCA and FBAR is ruled to be unconstitutional one might want to make sure the statute of limitations for general claims against the Government does not expire so that impediment to having FBAR penalties returned would not exist.

A statute of limitations is the deadline for filing a lawsuit. Most lawsuits MUST be filed within a certain amount of time. In general, once the statute of limitations on a case “runs out,” the legal claim is not valid any longer.  
When you sue a government agency, you first have to file a special claim (called an "administrative claim") with the government office or agency before you file in court. You have to use the government’s form to file the claim. Claims against government agencies: You must file a claim with the agency within 6 months (for some cases, 1 year) of the incident. If the claim is denied, you can then file your lawsuit in court but there are strict limits to when.
After you file your claim, the government has 45 days to respond.  If the government agency denies your claim during the 45 days, you have 6 months to file a lawsuit in court from date the denial was mailed or personally delivered to you.  If you do not get a rejection letter, you have 2 years to file from the day the incident occurred.  But do not count on having 2 years to file your claim.
The statute of limitations for government claims can be complicated to figure out.
Government Code sections 912.4, 912.6.
Government Code section 945.6 (a)(2).